Efficacy and safety of rofecoxib in patients with chronic low back pain: results from two 4-week, randomized, placebo-controlled, parallel-group, double-blind trials.

Study Design: Two replicate, 4-week, randomized, double-blind, placebo-controlled, trials of rofecoxib 25 and 50 mg versus placebo for chronic low back pain.

Objectives: To determine the efficacy and safety of two doses of rofecoxib compared to placebo in the treatment of chronic low back pain.

Summary Of Background Data: Although nonsteroidal anti-inflammatory drugs are commonly prescribed for chronic low back pain, their efficacy is unproven and toxicity can be serious. These studies evaluated the efficacy and tolerability of rofecoxib, a selective COX-2 inhibitor, in the treatment of chronic low back pain.

Methods: Patients with chronic low back pain were randomized 1:1:1 to rofecoxib 25 mg, 50 mg, or placebo once daily. Primary endpoint: Low Back Pain Intensity. Secondary endpoints: Pain Bothersomeness, Global Assessments of Response to Therapy, Global Assessment of Disease Status, Roland-Morris Disability Questionnaire, SF-12 Health Survey, Use of Rescue Acetaminophen, and Discontinuations Due to Lack of Efficacy.

Results: Combining both studies, 690 patients were randomized to placebo (N = 228), rofecoxib 25 mg (N = 233), or rofecoxib 50 mg (N = 229). Mean (+/- SD) age was 53.4 (+/- 12.9) years, pain duration 12.1 (+/- 11.8) years, 62.3% female. Both rofecoxib groups improved significantly. Mean differences from placebo in pain intensity were -13.50 mm, -13.81 mm (25, 50 mg doses) respectively (P < 0.001). Both regimens were superior to placebo in eight of nine secondary endpoints. Fifty mg provided no advantage over 25 mg. Both rofecoxib regimens were well tolerated, although 25 mg had a slightly better safety profile.

Conclusions: Rofecoxib significantly reduced chronic low back pain in adults and was well tolerated.